In wire bonding operations, for example where it is desired to connect the lead wires from a semiconductor component to bond pads formed on a substrate, an ultrasonic welding operation is carried out using a transducer that is caused to vibrate at ultrasonic frequencies. A conventional transducer comprises a piezoelectric element for generating ultrasonic vibrations, an ultrasonic amplifying horn and a bonding tool which is normally in the form of a capillary or wedge. The bonding tool is located at the free end of the amplifying horn and is used to apply the bonding force to the components being welded together.
The amplifying horn is normally provided with a flange or other form of mounting member, often known as a barrel or collar, that permits the transducer to be mounted to a wire bonding machine for movement in the X, Y and Z axes (and also in some designs about a θ axis) as required in a sequence of bonding operations.